1. Field of the Invention
The invention relates to a disk cartridge and a disk drive for data storage, and more particularly, the invention relates to a disk cartridge with a rotatable cartridge door and a disk drive with a mechanism for opening the cartridge door.
2. Brief Description of the Related Art
Data storage disk systems employing removable disk cartridges are generally used to add additional hard drive storage to a computer system or to provide backup storage capacity. The disk cartridges may contain either a single disk or more than one disk each having two recording surfaces. The disks within these disk cartridges are generally optical or magnetic disks of varying sizes and storage capacities.
Removable disk cartridges for storing digital electronic information typically include an outer cartridge housing containing one or more rotatable storage medium or disk upon which electronic information is stored. The cartridge housing includes upper and lower housing members which are joined together to protect and house the disk. The disk is mounted on a central hub assembly which holds the disk and allows the disk to rotate within the cartridge housing when data is being read from or written to the recording surfaces of the disk. When the disk cartridge is inserted into a disk drive, a spindle motor in the disk drive engages the disk hub in order to rotate the disk within the housing as a read/write head reads or writes data from or to recording surfaces of the disk.
The disk cartridge housing generally includes some form of an opening to provide the read/write head of the disk drive with access to the recording surfaces of the disk. A shutter or door mechanism is often provided which covers the cartridge opening when the cartridge is not in the disk drive to prevent damage to or contamination of the recording surfaces of the disks. As the disk cartridge is inserted into the disk drive the door mechanism is opened by a door activator of the disk drive to allow access to the recording surfaces of the disk.
One type of disk cartridge door commonly used is a sliding metal door which is mounted on an outside of the disk cartridge housing and slides laterally in grooves on the outside of the housing. This type of sliding door is opened when inserted into a disk drive by a moving door activator in the disk drive.
Rotatable cartridge doors are also known which are opened by a pivoting lever arrangement in the disk drive. The pivoting lever pushes against a tab on the outside of the cartridge door to open the door. These conventional lever arrangements for opening the rotatable disk cartridge doors increase the size of the disk drive.
Another type of disk cartridge door used when less vertical space is available is a metal band type door. The metal band is mounted between the top and bottom walls of the disk cartridge housing and slides in circular grooves formed in the top and bottom walls of the cartridge housing concentric with the disk. A portion of the band type door protrudes outside the disk cartridge and is engaged by an opening member inside the disk drive to open the door. However, the band type disk cartridge door assemblies have problems with particulate generation due to the engagement of sharp metal edges of the metal band door with the plastic cartridge housings. In addition, relatively thick top and bottom cartridge walls are required to form the grooves in which the metal band slides.
Accordingly, it would be desirable to provide a disk cartridge door assembly and door opening mechanism which requires a minimum vertical space. Further, it would be desirable to provide a door assembly in which all bearing interfaces have low friction and low wear to reduce particulate generation.